1. Field of the Invention
The present invention relates to a rear lamp unit for a vehicle such as a motorcycle.
2. Description of Background Art
A rear lamp unit for a vehicle such as a motorcycle includes a tail lamp which is illuminated for identifying the presence of the vehicle to the rear, and a brake lamp which is illuminated for notifying that the vehicle is in a braking action, and so on. In the rear lamp units, a plurality of light-emitting diodes (so-called LED) are used as a light source. For example, see JP-A-2003-54460. In such a rear lamp unit, a flexibility in the design of the rear lamp unit and the rear portion of the vehicle body is such that the shape of the lens which is large in ratio can be set easily. This design is employed in many vehicles in recent years.
Since the illumination of the light-emitting diode has high directivity, there is a case where an outer lens is disposed in the illuminating direction thereof which is formed with a predetermined cut pattern to diffuse light. Thus, a widening of the light-emitting area results.
However, the cut pattern formed on the outer lens is located close to the outer surface of the vehicle so that it can be seen easily from the outside. Thus, the pattern may affect the appearance of the vehicle. Therefore, a rear lamp unit which can be provided with the cut pattern in relation to the appearance of the vehicle and can secure a predetermined light-emitting area is needed.